Red fox decline linked to coyotes

Local hunters won’t be surprised to hear that coyotes’ gain in Nova Scotia has been red foxes’ loss, according to a study published last week.

White-tailed deer also declined when coyotes arrived in the province about 35 years ago.

Two researchers at Oregon State University used fur-trapping records to track the fortunes of three predators on the East Coast and in the northwest.

“The result in particular in Nova Scotia is quite compelling, because you can see coyotes enter the fur-trapping data … and they increase almost exponentially as red foxes decrease,” said Thomas Newsome, a co-author of the study, which was published in the Journal of Animal Ecology.

All data showed that the ascension of coyotes is linked to the decline of red foxes, which compete with coyotes for food.

Coyotes, in turn, compete and generally lose to wolves when they are present, but Nova Scotia has had no wolves for at least a hundred years, said Newsome.

He and co-author William Ripple compared Nova Scotia, New Brunswick and Maine — all with no wolves — with Alaska, the Yukon and the Northwest Territories, where there are large wolf populations. They found that by keeping coyotes in check, wolves allow red foxes to thrive.

Coyotes are relative newcomers to Nova Scotia, arriving in about 1980, said Newsome. Their numbers shot up quickly.

“It only took coyotes about 20 to 30 years to outnumber red foxes in Maine, Nova Scotia and New Brunswick,” he said in an interview.

Red fox numbers dropped off most dramatically in Nova Scotia, he said. Unpublished research by the province showed the arrival of coyotes also coincided with a decline in white-tailed deer. According to his data, the coyote population continued to rise.

“From fur-trapping records we have it going to 2010, and it’s continuing to go up.”

Records from 1980 showed zero coyote pelts, and there were 2,500 in 2010, he said.

The Natural Resources Department says the coyote population has levelled off, but a local coyote researcher says that may only have happened very recently.

“I know in the last few years that, at least from the information I’m getting from DNR, the populations have stabilized,” said Carly Sponarski, a PhD student at Memorial University who researches coyote-human interactions in Cape Breton.

“Animal populations in general are always in flux, so stabilizing is a relative statement,” she said.

“Coyotes are new to our area. Foxes have been here longer. It takes a while for the system in general, and I’m talking about everything from plants to wildlife, to come to a kind of equilibrium, but that equilibrium always shifts through time.”

According to the Natural Resources Department, red foxes are present across Nova Scotia, usually in agricultural areas mixed with woodland. Like coyotes, they eat small rodents, other small animals and fruit and sometimes scavenge human food or carrion.

Newsome said he expects the study to factor into discussions about reviving the American wolf population.

Wolves disappeared for 70 years from the 48 contiguous American states, but in the mid-1990s, captured Canadian wolves were used to reintroduce the species to Yellowstone National Park and Idaho.

Since then, the predators have spread into Oregon and the state of Washington, now occupying about 15 per cent of their former range across the U.S, he said.